ABSTRACT Project 5 Co-Development of Skills Associated with Learning Difficulties/Disabilities in Monolingual and Bilingual Children The successful acquisition of reading and math skills during elementary school represents one of the most significant educational achievements of early education. These skills provide the foundation for acquiring knowledge both in school and throughout life. Many children acquire these skills early and maintain them at a high level throughout school. A significant number of children, however, struggle with reading skills, math skills, or both throughout their school experiences, resulting in learning difficulties and disabilities. Two factors that may affect development and co-development of reading and math are self-regulation and non-mainstream language environments (i.e., children from homes in which a language other than the societal language is spoken). Whereas prior research has demonstrated associations between these two factors and problems in reading and math, including learning disabilities in these domains, few studies have employed longitudinal designs that allow a determination of the nature and direction of these associations. Consequently, the overall goals of this project are to examine issues related to the development and co-development of learning disabilities and difficulties in reading and math both in the context of self-regulation and in the context of nonmainstream language environments across the early-elementary-school years using longitudinal-study designs that allow better determination of the nature of the associations. Three studies--(a) A longitudinal study of co-development of reading, math, and self-regulation in early elementary school in (primarily) monolingual English-speaking children that builds on one of our current LDRC samples; (b) A longitudinal study of co- development of language, reading-related and, math skills, as well as self-regulation from preschool to 2nd grade with Spanish-speaking English-learners; and (c) An eye-movement study of Spanish-speaking children's reading in English and Spanish to identify lexical and reader characteristics associated with difficulty acquiring meaning from text)--will be used to address five specific aims: (1) Examine how co-development of reading and math skills across the early-elementary-school period is related to success or difficulty in both areas. (2) Identify the influences of self-regulation, indexed by executive function (EF) and behavior in the classroom, on children's reading and math development and co-development across the early-elementary-school period. (3) Explore the co-development of early language, reading, and math skills in Spanish and English for children whose home language is Spanish and examine how early development of these skills relates to developing risk of learning difficulties or disabilities in language, reading, and mathematics in kindergarten through 2nd grade. (4) Determine how the development of self-regulation of Spanish-speaking preschoolers represents risk or protective factors for learning difficulties or disabilities in language, reading, and math in kindergarten through 2nd grade. (5) Identify potential differences in how word- and child-level factors affect children's moment-to-moment reading behaviors (i.e., eye movements) while reading Spanish and English text.